as a kid, he was obsessed with science, astrong me, physics, he fell in with the wrong crowd, became a father too soon and lost his job and home. >> this guy patrick walks up. >> reporter: yeah. >> and says can i talk to you? >> yeah. >> reporter: what goes through your head? >> wow. >> reporter: what did you think he wanted? >> i didn't believe anything. you got the wrong guy. no, he just said hey, i have something strange but i'm pushing an offer and instantly i just said, in my mind, door number two. >> reporter: and then, the stranger actually showed up with an actual laptop, and those lessons turned into an obsession. he would write code for hours, for days on the banks of the hudson or in a nook in pratt trick's office. at night, patrick would go home and leo would go outside. shelters aren't his thing, which seem fine until winter blew in. how do you stay warm on the really bitter nights? >> you go to the train station. >> reporter: yeah. like tons of blankets. >> it's getting really cold and i keep telling him this. he's like i'm good, man, let's keep going. >> reporter: patr